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Notes from Spring, 2016, MIAAPT Meeting

Below find my notes from the Spring 2016 MIAAPT meeting, held at Cranbrook, Bloomfield Hills, MI. As always my notes are just my notes – accuracy is not guaranteed, and they reflect what I found interesting, not necessarily a good representation of what was actually said.

Modeling Mechanics with Google Sheets, Don Pata

Talked about creating spreadsheets in Google Sheets to model (usually) kinematics behavior. Two things that struck me in particular – when creating a graph that shows velocity as a function of time *with air resistance*, if the initial speed is greater than terminal velocity you see the object slow down as it falls, which students find intriguing. Second, similar to LCC’s PHYS251 “Energy Conservation” lab they make an plot with experimental data showing a mass oscillating on a vertical spring, kinetic energy, potential energy, and total energy all plotted together as a function of time, total energy is just a flat line, looks beautiful.

He wrote a nifty app: http://websites.delta.edu/michaelfaleski/SpaceCollision.html , that allows you to collide a sticky object with a rod in space, with or without the pivot point of the rod fixed. Results that surprised him – for certain arrangements of the pivot point and object, the center of mass of the system actually moves backwards after collision. Second, if you want to maximize the angular velocity of the system after collision, you do NOT want the object to hit right on the end of the rod. There is a give and take between the increased torque, and the increased moment of inertia, that makes the best collision point just a little closer to the pivot point.

Creating a Mental Model of a Radian, James DeHaan

When he asks his students to define a radian, their answers generally amount to either, “there are two pi of them in a circle” or “it is about 57 degrees”. Talked about how a radian is really a non-arbitrary (unlike degrees) angle measure, the ratio of an arc length to a radius.

The Natural Human Electricity and its use to Operate Touchscreens, Wathiq Abdul-Razzaq

Said students think Physics labs are boring, there are no chickens hatching, we need to give them more exciting titles, like the title of his talk. Said that when a human finger touches a touchscreen that amounts to a capacitance of about 100 pF. Talked about a nifty demo where he physically wedges a battery between two (large) capacitor plates hooked to a voltmeter, then removes the battery, voltmeter reading does not change. Talked about charging those plates from the static electricity of his students.

Experimenting with Impacts, Michael LoPresto

Talked about a simple lab they do in which they drop steel balls, of different masses and from different heights, into a tub of sand. Students then measure the rim diameter of the ejected material. They then plot the rim diameter on the y-axis, initial potential energy on the x-axis. He cited a paper which showed that if most of the energy goes into ejecting the material the graph goes like E^1/4, whereas if most of the energy goes into digging the hole the graph goes like E^something_I_forget. In any case students get something close to E^1/4. A questioner mentioned that Purdue has an “Impact Earth” app that does similar theoretical calculations.

Cheap Sensors Allow for Real Questions, Steve Dickie

Talked about how the Maker Movement has resulted in many cheap analog sensors. These sensors can actually be integrated with LoggerPro – you can purchase a Vernier cable with analog LabPro connector on one side, just loose wires on the other side, and attach your maker movement sensor. LoggerPro will just record the voltage as a function of time, but you can add a calculated column to give the quantity you actually want. They purchased some $30 accelerometers which they embedded in football helmets they then attacked with hammers. In summary – sensors cheaper and more capable that a lot of the stuff you buy from Vernier.

Flipping a Class Without Flipping Out, Alan Grafe

Talked about the practical aspects of flipping a class. Uses Notability for drawings, Camtasia for recording and editing.

Talked about assigning grades based on mastery of certain standards, rather than traditional grading. Has 5-10 standards per unit, all standards are pass/fail, requires perfection for pass. Subsequent reassessments get harder. Has seen her AP passing rates go up, not sure how much of that is due to grading change.

Building a Culture for Learning Physics, Bryan Battaglia

“Failure is always an option.” “Physics is not the most important thing. Love is.” ~Feynman

Using Science Olympiad Events to Bring Engineering and Design Into the Classroom, James Gell

Talked about using SOINC events to help meet NGSS engineering standards, and how much students love these activities. Especially talked about a boomilever design project, boomilever must hold 15 kg out at 40 cm, students building boomilevers with a mass of only 11 g that can do this. At national SOINC masses get down to 6 g.

Why do we Teach Physics Like It’s 1899?, Vance Nannini

Students love space stuff. Mentioned how much they love NASA “Seven minutes of terror” video about Curiousity lansing. Talked about gravitational assists, elastic collision, inbound and outbound velocities of spacecraft same from perspective of the planet, from sun’s perspective outbound is much larger, planet orbit radius does shrink by a tiny amount. Gravitational assist theory was developed in the 1920s. “Suck less every day” his motto.

Physics of clustering and invasion of living cells, Evgeniy Khain

Hard to summarize the keynote. Studies cancer cells from a theoretical perspective, with experimental partners who study the cells in petri dishes. The cells will migrate their own diameter in 5-10 minutes – this is just a diffusive motion because they are in a fluid, so the distance they travel goes like the square root of time. Time for cell division is about a day.

He specifically studies brain tumors – median survival time is about 12 months. There are sort of three cell behaviors involved. Cells in the inside of tumors don’t do much because they haven’t the room. Cells on the edges of tumors have a rapidly dividing phenotype. And then sometimes cells detach from tumors and have an invasive phenotype – for reasons not well known, the division rate of these cells falls by a factor of 10. That might seem like a good thing, but the problem is radiation and chemotherapy target dividing cells, so the invasive cells are relatively invisible to those treatments.

He then developed a stochastic model to describe division, proliferation, and adhesion, in which cells begin at random locations in a 2-dimensional gridwork, and are then permitted to diffuse, divide, and stick together according to parameters chosen by the simulation. Clusters of cells will form, or not, based on the adhesion parameter, but the surprise was there is actually a phase transition, a certain adhesion parameter at which, suddenly, cluster formation becomes possible. This has also been verified experimentally. If clusters do form, the phenotype of some cells will switch to proliferative, and a recurrence of the tumor may occur.

However, even if the adhesion parameter is too low spontaneous clustering can occur if enough cells “random walk into the same room”, and hang together for long enough (about an hour) for the phenotype to change. In a 3 mm by 3 mm system this will happen in roughly 4 days.

Business Meeting

Fall meeting, which will be at LCC, will be coordinated with MSTA. Teachers are interested in having higher ed help show them how to implement NGSS engineering standards. One high school teacher mentioned he would love help putting together specific labs and projects. The thought is that some long-term partnerships might form to this end.

Alex Azima, “We’re interested in stuff”.

Taoufik Nadji was elected new 2nd VP.

EHW and Reflections in Physics Curriculum, Taoufik Nadji

Talked about the need for student reflection on what they have learned, and this email reflection homework he has his students turn in every two weeks. They must follow specific guidelines to reflect, question, and feel. Reflect – summary of concepts they understood, must quote something from the textbook with page number and something from lecture. Question – summary of concepts they would still like to understand. Feel – a transfer summary of how they felt about what they learned, perhaps applying it to the rest of their life.

Circular Motion – Lo-Tech to Hi-Tech, Daniel Lorts and Frank Norton

Demonstrated a rotating platform they use to help teach rotation consisting of a 24″ lazy-susan base supporting a larger wooden circle. First demo, put tube of fluid on circle, showed how angle of water depends upon location and speed. Also attached a Vernier cart by rubber band, then spring scale, to get a measure of forces. Did some neat demos where you lightly hold a ball on the rotating surface as well, then let it go.

Principles for Smart Teaching, Samanthi Wickramarachchi

Played a fun game to show that active learning aids memory. Showed 14ish word pairs where, in seven cases, you had to think for two seconds to complete one of the words, in the other seven cases you were just given both. Five minutes later people remembered better the word pairs they had to think about.

At Lawrence, lab and lecture are still strictly divided, and the lab is only one credit – what does that say about how much we value lab work? How much attention do instructors even pay to lab reports? How much do students care when they only get them back two weeks after they do the lab? They are trying to make changes so students do meaningful writing and get immediate feedback upon leaving lab, and also trying to make the labs less “do this, then this, then this…”. Results have been good so far, students who get bad feedback even wanting to repeat parts of labs to improve their score. He mentioned students lose 25% if they blow a fuse in lab!

Talked about attempts to incorporate computational physics into introductory physics in an MSU course called “Projects and practices in Physics”. The course involves a mix of analytic and computational methods. Some students have no coding experience, so they use visual Python or are given minimally working programs they modify. One example problem is a simulation of the motion of a satellite bound to the Earth.